To facilitate recycling of waste, it has become common practice to dispose and collect recyclable waste separately. Taking account of the sorting skill and motivation of the general public and to maintain an acceptable efficiency of collection and handling, the number of separate categories into which waste is to be separated upon disposal is limited by collecting several categories of recyclable waste material in mingled form. Separately collected recyclable waste generally comprises metal (sometimes excluding aluminium), plastic and glass.
After collection, generally glass, plastics, metals responsive to magnetism (mainly steel) and, if present, metals not responsive to magnetism (mainly aluminium) are industrially separated from the mingled recyclable waste.
An apparatus and a method for separating recyclable waste materials is described in U.S. Pat. No. 5,116,486.
In this known apparatus, the separating process is carried out by first passing the waste material along a magnetic separator such as a magnetic pulley at an end of a belt conveyor for separating parts of magnetic-responsive material (mainly steel) from the other material. The remaining material is passed from the end of the conveyor belt into a second stage in which the remaining material is passed over a vibrating screen to separate parts smaller than a predetermined size from the other remaining material. From the vibrating screen the remaining material is introduced to an elongated slide along which an air stream separator is positioned. The air stream separator provides a stream or current of air in a direction transverse to the direction of movement of the remaining material carrying away specifically lighter materials such as plastic and aluminium cans from the heavier, mostly glass objects, which remain in the slide, and discharging the specifically lighter objects onto a second conveyor along which manual sorting can take place. Finally, the heavier objects are deposited onto a third conveyor along which manual sorting can also take place.
A problem of apparatuses such as the above described known apparatus is that breaking of glass objects occurs very frequently. Preferably, glass objects should remain intact to facilitate further sorting, for example with respect to colour, and to reduce the injury-risks of personnel if the further sorting is carried out manually.
Another problem is, that manufacturing costs of the combination of such apparatuses, in particular of the vibrating screen devices and the like, are high.
Still another problem is, that during operation, the known apparatuses emit undesirably much noise.
The invention is aimed at providing an apparatus for separating recyclable waster material, and in particular an apparatus for separating small objects out of recyclable waste, in which breakage of glass objects occurs less frequently.
The invention is also aimed at providing an apparatus for performing the above-mentioned function which is of a simple, light and cost-efficient construction.
Furthermore, it is an object of the invention to provide an apparatus for performing the above-mentioned function which emits less noise during operation.